Automatic grab.



G. LAUDI.

AUTOMATIG GRAB.

APPLICATION FILED OUT. 15, 19170.

1,0Q8,345, Patented Nov. 14, 1911.

KM M

coLuMmA PLANOG c.

AVAIL/awe...

mural) STATES om LAUDI. or nosssLnoar-enaifliiannno,

atrrom'no GRAB."

To all whom it may concern:

Be it known that I, CARL LAUDI, a citizen of Germany, residing at 407Grafenberger Allee, Dusseldorf-Grafenberg, have inventetl certain newand useful Improvements in an Automatic Grab, of which the following isa specification.

The present invention relates to that kind of automatic grab in whichfor the purpose of obtainin a considerable and graduallv lit increasingc osin r force, the grab jaws which are pivoted to tie lower cross baror axle of the tackle are closed by means of a togglelcver mechanism. Incontradistinction to the known devices of this kind the toggle leverjoint of the improved grab according to the resent invention is actedupon by the upper lilock and the em it ing cord or rope, while the freeon... 0 0th arms of the toggle-lever mechanism are connected totriangular arrangements of levers which are pivoted to the outer ends ofthe jaws of the grab and turn on a common axis.

A constructional form of the improved grab is shown in the accompanyingdrawings by way of example, Figure 1 being an elevation representing thegrab in its closed position, while Fig. 2 is a similar representation ofthe grab in its open position.

The two jaws of the grab are ivoted at a to the lower cross bar or axleo the tackle. livoted to the jaws at b, b are lever triangles f, g, It,which are adapted to turn about a common axis 0. The triangles areconnected at cl, (1 to the toggle lever mechauism (1,0 which is actedupon at its joint i by the upper block of the tackle or an equivalentpart and the emptying cord or rope 3.

The automatic opening of the jaws has hitherto been accomplished by theweight of the lower cross bar and part of the weightof the jaws,additional weight being in many cases placed on the cross bar foretfectin the opening. An automatic grab shoul however not only openautomatically, but the pull exerted by the cord or rope upon the windingdrum of the hoisting apparatus should be sufiicient to rotate the drumso as to obviate the necessity of driving the hoisting up )aratusbackward b motive ower. In the improved grab formin the subject of thepresent invention the w ole weight of the rab with the exception of theupper block of the tackle comes into play durm the opening, the wholegrab being suspende EM me Specification of Letters Iaton t. Pat ntedNov". 14:, 1911. Application filed October 15, 1910. Serial No. [587,236.

g t! from the emptying cord qr ropbjl at i and a particularly strongpulling force 1s exerted on the toggle leversduri g the" lllltlakperiodof the opening move ent'bfthifrab.

to the jaws by means of the lever triangles f, g, h. turning upon theiraxis a and are also transmitted to the lifting rope or cord 4 andconsequently to the drum of the hoisting rotated backward and a savingof motive power and labor is obtained.

In order to obtain the greatest etliciency and the most advantageousfilling proportion of the rab the followin should be ful lled: Aconsiders )le width of the jaws, a comparatively small weight of thegrab proper, a large closing power, an advantageous osition of the aws,and a lar e opening oree.

t Wlll be seen that there are two lifting cords 4 and two em tyin cords3. The lifting cords serve w ien t e grab is in its open position forclosing the same, and serve a oted to the lower cross bar of a tackleand actuated by a to 'gle lever mechanism for the purpose of o tainin agradually increasing closing force, t e combination of a to g e of t etackle operatively connected to the joint of the toggle leveirmechanism, an emptying cord also connected to the said toggle leverjoint, and t v0 lever triangles nected at their outer ends to the endsof the toggle levers and pivoted to the jaws of the gra 2. In automaticgrabs having jaws piv- These large pulling forces-are! transmittedapparatus. The drum is thus automatically conditions so after closingthe grab for lifting the is to be opened this is etlected by put- 5 Ofcourse this means that dur- 1. In automatic grabs having jaws pivlevermechimisni, an upper block adapted to turn on a com non axis and con 10boted to the lower block of a tackle, the com- 1 in 1e lower block, anuvers pivoted to the up ing cord fixed to the u mediate parts pivotedtoggle levers and the connected to each othei,

perfglecli, toggle lesignature in presence of two witnesses. per cc anemptyn per bIpcl, and inter- CARL to" the ends of the Witnesses: jawsand pivotally H. Sonnoxm,

Loms VANDOBY.

Washington, D. 0.

m5 piveted to In tes tiimcny whereof I have M's'ixed m Copies of thispefiem: 174 Bbteincfi for five cents each, by addressing thecommissioner oi Eastern:

